add function to calculate the GRSex score using a SDM

[dcarver1]

Fill in additional requires as needed here.

[dcarver1]

This is drafted out and should be largely functional. Working off fork on my repo.
Added as a stand alone function and utilizes the existing buffer method.

Needs testing so producing a model for QUAC is the next step so we can apply the full workflow.

Need to provide conditional step in the workflow to evaluate if an SDM is present and determine which of the output measures is being used the vector or sdm based method. I think we want one or the other rather then two results?? Need to think about that some.